Function ostn02_phf::ostn02_lookup

pub fn ostn02_lookup(key: &str) -> Option<(i32, i32, i32)>

Return a 3-tuple of Easting, Northing, and height adjustments, for use in transforming ETRS89 Eastings and Northings to OSGB36 Eastings, Northings.
The key is the combined hex-transformed (03x) kilometer-grid reference of the Northings and Eastings:

Examples

use ostn02_phf::ostn02_lookup;
 
// Caister Tower Eastings and Northings: 651307.003, 313255.686
let e_grid = (651307.003 / 1000.) as i32;
let n_grid = (313255.686 / 1000.) as i32;
let key = format!("{:03x}{:03x}", n_grid, e_grid);
// key is 13928b
let result = ostn02_lookup(&*key).unwrap();
// result should be (16500, 3359, 270)
assert_eq!(result, (16500, 3359, 270));
// remember that the actual adjustment for a coordinate is a bilinear transform, using a square
// see ostn02_shifts in https://github.com/urschrei/lonlat_bng/blob/master/src/ostn02/mod.rs